When adding the ESP32 backpack for HDZero a bug crept in because a compile-time check was inserted for the platform which had ESP8266 before NAMIMNO, but NAMIMNO backpack is an ESP8266 (but targets an STM32) and so it broke the upload begin call!
Rearranged the checks to fix this and renamed the flag to STM32_TX_BACKPACK as it's not just used for the Namimno modules, I use it on R9M too.
When adding the ESP32 backpack for HDZero a bug crept in because a compile-time check was inserted for the platform which had ESP8266 before NAMIMNO, but NAMIMNO backpack is an ESP8266 (but targets an STM32) and so it broke the upload begin call!
Rearranged the checks to fix this and renamed the flag to STM32_TX_BACKPACK as it's not just used for the Namimno modules, I use it on R9M too.